It's official: we're hooked on free mobile games and our habit may be getting slightly out of hand.

Are you reading this while out and about? Just humour us and stop for a minute to take a look around.

Chances are you're not the only one who's been looking intently down at their phone, because if there's one thing we can't stop doing, it's whipping out our mobile at every opportunity.

However it's not riveting emoji-filled conversations that have caught our attention – Britain has caught the gaming bug, with one-in-10 people admitting they're addicted to at least one free mobile game, according to research by Gocompare.com.

But with in-app purchases offered every two minutes, your 'free' addiction could actually become quite a costly habit…

Fight club

So which apps are cashing in the most on their loyal fan-base of addicted players?

Unsurprisingly war strategy games claimed three positions in the top four highest grossing games on the Apple app store.

Clash of Clans and Mobile Strike both made an appearance. But blasting the others out the water, is Game of War – Fire Age which makes over £1m per day.

Mum's favourite, Candy Crush Saga, cropped up near the top as well, making just over £300,000 per day. Not to be sniffed at.

"However, while something like a £2.99 purchase once a week may not seem like much, it can add up to over £150 a year and some may find they're spending a significant amount of money on a 'free' game."

The young ones

It's not just adults who are disengaging their brain to indulge in a spot of online gaming either.

Nearly one-in-10 parents have registered card details on their kid's phone, enabling them to make purchases.

We certainly weren't worthy of that type of trust as children and in some cases we wonder if it's right to be wary.

There are umpteen stories floating around the internet of kids racking up thousands of pounds on their parent's plastic with in-app purchases.

But before you seize the iPhone from your kid's hand, it's worth realising that those are extreme cases, with £19.32 being the actual average spend on in-app purchases by nippers. Mind you, that's still a fair few bags of gems on Clash of Clans…

It can be as easy as a click of a button to charge in-app purchases to your account, so you may want to keep an eagle eye on your kid when they're in game mode.

Or, you can change the settings to make it necessary to enter your card details or a password each time a purchase is made.